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Title: Computer study of physical properties of silicon nanostructures

Abstract

The method of molecular dynamics is applied to the study of variations in the physical properties of vitreous and amorphous silicon nanoparticles when heated from 300 to 1700 K. The nanoparticles consist of 300, 400, and 500 atoms. The energy and the average length of the Si-Si bond are calculated, and the average number of bonds per atom is determined. Thermally induced strains tend to change the distribution of the excess potential energy among the concentric layers in the nanoparticles. It is shown that, energetically, the most preferential layer is the middle spherical layer of the 'warm' nanoparticle. The temperature behavior of the radial and tangential components of the atomic mobility coefficient in the concentric layers is considered. It is established that there is a liquid layer at the nanoparticle surface in the vicinity of the transition to melting. The vitrified Si{sub n} nanoparticles are kinetically more stable than the similar-sized amorphous particles.

Authors:
 [1]; ; ;  [2]
  1. Russian Academy of Sciences, Institute of Thermal Physics, Ural Division (Russian Federation), E-mail: galashev@ecko.uran.ru
  2. Russian Academy of Sciences, Institute of Industrial Ecology, Ural Division (Russian Federation)
Publication Date:
OSTI Identifier:
21088440
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 41; Journal Issue: 2; Other Information: DOI: 10.1134/S1063782607020157; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Ltd; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COMPUTER CALCULATIONS; LAYERS; MOLECULAR DYNAMICS METHOD; NANOSTRUCTURES; PARTICLES; PHYSICAL PROPERTIES; SILICON; STRAINS; SURFACES; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; TEMPERATURE RANGE 1000-4000 K

Citation Formats

Galashev, A. E., Izmodenov, I. A., Novruzov, A. N., and Novruzova, O. A. Computer study of physical properties of silicon nanostructures. United States: N. p., 2007. Web. doi:10.1134/S1063782607020157.
Galashev, A. E., Izmodenov, I. A., Novruzov, A. N., & Novruzova, O. A. Computer study of physical properties of silicon nanostructures. United States. doi:10.1134/S1063782607020157.
Galashev, A. E., Izmodenov, I. A., Novruzov, A. N., and Novruzova, O. A. Thu . "Computer study of physical properties of silicon nanostructures". United States. doi:10.1134/S1063782607020157.
@article{osti_21088440,
title = {Computer study of physical properties of silicon nanostructures},
author = {Galashev, A. E. and Izmodenov, I. A. and Novruzov, A. N. and Novruzova, O. A.},
abstractNote = {The method of molecular dynamics is applied to the study of variations in the physical properties of vitreous and amorphous silicon nanoparticles when heated from 300 to 1700 K. The nanoparticles consist of 300, 400, and 500 atoms. The energy and the average length of the Si-Si bond are calculated, and the average number of bonds per atom is determined. Thermally induced strains tend to change the distribution of the excess potential energy among the concentric layers in the nanoparticles. It is shown that, energetically, the most preferential layer is the middle spherical layer of the 'warm' nanoparticle. The temperature behavior of the radial and tangential components of the atomic mobility coefficient in the concentric layers is considered. It is established that there is a liquid layer at the nanoparticle surface in the vicinity of the transition to melting. The vitrified Si{sub n} nanoparticles are kinetically more stable than the similar-sized amorphous particles.},
doi = {10.1134/S1063782607020157},
journal = {Semiconductors},
number = 2,
volume = 41,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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